Polyprenyl phosphates have been well established as carriers in sugar transfer reactions involved in cell envelope polysaccharide biosynthesis in procaryotes and glycoprotein biosynthesis in eucaryotes. It is the objective of this research to study the mechanism and regulation of the biosynthesis of these polyprenyl phosphates in bacteria. Undecaprenyl pyrophosphate synthetase from Lactobacillus plantarum will be purified to homogeneity using in part preparative polyacrylamide gel electrophoresis and hydrophobic affinity chromatography. The enzyme will be characterized with regard to the number of polypeptide components, amino acid composition, and peptide maps. A variety of substrate analogues will be tested with the synthetase to examine the properties of the enzyme's catalytic site and a proposed scheme for termination of product elongation. A number of site-specific radiolabeled compounds, including photoaffinity reagents and arginine specific reagents will be synthesized and reacted with the synthetase. Peptide maps of the modified enzymes will be made and interpreted to gain information about the substrate and product binding domains.